Sorry, forgot to include my spec:
Hewlett Packard Presario CQ56 Notebook PC
AMD V160 Processor 2.4 GHz
RAM - 6 GB
64 Bit OS
AMD M880G with ATI Mobility Radeon HD 4250
That notebook is way underspecced for PR and this material. See: Adobe Forums: System requirements for CS5
AMD is lousy to begin with, 6 GB RAM is minimum, ATI does not support hardware MPE, not enough 7200 RPM SATA disks, etc. But hey, don't shoot the messenger...
Thanks for your reply, guess I'll just have to carry on with SD footage on Premiere. Strange how it seems to play HD fine on After Effects and Media Composer Though? Never mind
I looked over the Benchmark Results and found only a single AMD laptop, a Phenom II N930 with an ATI HD5470 video card, but that system is more than 35 times slower than a fast destop, despite having a separate 7200 RPM hard disk. It ranks at #844 out of 882 systems.